Preparation of N-phenyl-(S)-prolinol-derived P,N-ligands and their application in Pd-catalyzed asymmetric allylic alkylation
摘要:
Several NPN-type ligands bearing two chiral pyrrolidinyl groups derived from N-phenyl-(S)-prolinol were prepared by two synthetic methods. Their palladium-complex-catalyzed asymmetric allylic alkylation of malonates with 1,3-diphenyl 2-propenyl acetate delivered the products with good to high enantioselectivities (84-97% ee), including an optically active fluorine-containing compound. (c) 2006 Elsevier Ltd. All rights reserved.
已经测量了从广泛的路易斯碱硼烷加合物中置换 BH 3的奎宁环动力学。这些速率的参数化使得能够开发出离核量表 (NF B ),以量化和预测一系列其他路易斯碱基的离去基团能力。在多个系列 R' 3– n R n X (X = P, N; R' = 芳基, 烷基) 中观察到的可加性允许制定相关的取代基参数 ( n f PB , n f AB ),提供了一种方法计算N F B一系列路易斯碱基的值远远超出了实验得出的值。通过取代基参数n f PB与一系列烷基和芳基 MIDA 硼酸盐在中性条件下的水解速率的相关性,探索了核离性参数的效用。这允许鉴定具有接近反应中心的杂原子的 MIDA 硼酸盐,显示出不寻常的动力学不稳定性或水解稳定性。
from 1.34 +/- 0.02 x 10(-3) to 51 +/- 3 mol(-1) dm(3) s(-1) for P(2-OMe-C(6)H(4))(3) to PCy(3) respectively. Activation parameters range from 27 +/- 1 to 49.0 +/- 1.3 kJ mol(-1) for DeltaH(double dagger) and -112 +/- 9 to -140 +/- 3 J K(-1) mol(-1) for DeltaS(double dagger) supporting a S(N)2 mechanism in which the initial nucleophilic attack of P on Se is rate determining. Reaction rates are promoted
Versatile Visible‐Light‐Driven Synthesis of Asymmetrical Phosphines and Phosphonium Salts
作者:Percia Beatrice Arockiam、Ulrich Lennert、Christina Graf、Robin Rothfelder、Daniel J. Scott、Tillmann G. Fischer、Kirsten Zeitler、Robert Wolf
DOI:10.1002/chem.202002646
日期:2020.12.9
Asymmetrically substituted tertiary phosphines and quaternaryphosphonium salts are used extensively in applications throughout industry and academia. Despite their significance, classical methods to synthesize such compounds often demand either harsh reaction conditions, prefunctionalization of starting materials, highly sensitive organometallic reagents, or expensive transition‐metal catalysts. Mild
NCN pincer palladium complex was developed as a probe molecule to index the coordinationability of various monodentate ligands. Coordination constants of 27 monodentate ligands (L) with a pincer palladium complex to form complexes of the type ArPd(L)2Cl were determined by 1H NMR spectroscopy. This allowed the coordinationability of a wide variety of ligands, including P-coordinating ligands (phosphane
[EN] METHOD FOR MANUFACTURING A BORONIC ACID ESTER COMPOUND<br/>[FR] PROCÉDÉ POUR LA FABRICATION D'UN COMPOSÉ ESTER DE L'ACIDE BORONIQUE
申请人:SUMITOMO CHEMICAL CO
公开号:WO2010110782A1
公开(公告)日:2010-09-30
The present invention relates to a method for manufacturing a boronic acid ester compound, characterized by reacting an aryl halide compound and a diboron ester compound in the presence of a nitrogen-containing organic base, a nickel catalyst, a phosphine compound and a solvent. According to the manufacturing method of the present invention, even if a nickel catalyst is used as the catalyst, a desired boronic acid ester compound can be obtained in a sufficiently high yield. Furthermore, even if aryl chloride or aryl bromide having relatively low price and low reactivity, was used as the aryl halide compound, a desired boronic acid ester compound can be obtained in a sufficiently high yield.
METHOD FOR MANUFACTURING A BORONIC ACID ESTER COMPOUND
申请人:Miki Takashi
公开号:US20120123122A1
公开(公告)日:2012-05-17
The present invention relates to a method for manufacturing a boronic acid ester compound, characterized by reacting an aryl halide compound and a diboron ester compound in the presence of a nitrogen-containing organic base, a nickel catalyst, a phosphine compound and a solvent. According to the manufacturing method of the present invention, even if a nickel catalyst is used as the catalyst, a desired boronic acid ester compound can be obtained in a sufficiently high yield. Furthermore, even if aryl chloride or aryl bromide having relatively low price and low reactivity, was used as the aryl halide compound, a desired boronic acid ester compound can be obtained in a sufficiently high yield.